1. Field of the Invention
The present invention relates to ultrasonic transducers of the type employed to bond two metallic elements together. More specifically, the present invention relates to a more efficient transducer of the type used on automatic wire bonders and ultrasonic machines employed in the semiconductor and other industries.
2. Description of the Prior Art
Heretofore, it was known that dissimilar metals could be joined at relatively low temperatures by the simultaneous application of pressure and ultrasonic energy applied through means of bonding tools mounted on or in ultrasonic transducers. At least since the introduction of integrated circuits in the 1960s, semiconductors have been bonded to a substrate or carrier using ultrasonic energy and fine wires have been interconnected from lead out pads on the semiconductor die to leads on carriers, substrates and lead frames using bonding tools mounted in ultrasonic transducers.
Heretofore, ultrasonic transducers that were designed for use on flip chip die and wire bonders have remained substantially unchanged for years. Such prior art ultrasonic transducers comprise a large number of individual parts that are difficult to assembly. Once the prior art transducers were assembled, they had to be tested, sorted, tuned and reworked. It was common practice to trim metal from the transducer driver in an attempt to adjust the transducer to a desired frequency and/or to save the transducer as an operative device. Such transducers are known as having high "Q" systems.
It would be highly desirable to provide a radically new ultrasonic transducer that eliminates most of the problems associated with prior art ultrasonic transducers.